Citation Details

Journal Article

Animals; Antineoplastic Agents; Bioware; Brain Neoplasms; Cell Line, Tumor; Drug Implants; Glioblastoma; Male; Metabolic Clearance Rate; Mice; Mice, Inbred BALB C; Nanostructures; Paclitaxel; Treatment Outcome; U-87 MG-luc2

Pharmacokinetics and therapeutic efficacy of submicron/nanoscale, intracranial implants were evaluated for treating malignant glioblastoma in mice. 9.1% (w/w) paclitaxel-loaded polylactide-co-glycolide (PLGA) nanofiber discs (F3) were fabricated and characterized for morphology and size distribution. Along with F3, three other formulations, 9.1% (w/w) paclitaxel-loaded PLGA submicron-fiber discs (F2), 16.7% (w/w) paclitaxel-loaded PLGA microspheres entrapped in hydrogel matrices (H80 and M80) were intracranially implanted in BALB/c mice and the coronal brain sections were analyzed for bio-distribution of paclitaxel on 14, 28 and 42 days post-implantation. BALB/c nude mice with intracranial human glioblastoma (U87 MG-luc2) were used in the therapeutic efficacy study. Animals were randomized to intracranial implantation of F3 and H80 with paclitaxel dose of 10mg/kg, placebo F3, placebo H80, weekly intratumoral injection of Taxol (10mg/kg) or no treatment and the treatment response was analyzed by bioluminescence imaging and histological (H&E, Ki-67) examinations. Enhanced, therapeutic paclitaxel penetration (approximately 1 microm) in the mouse brain up to 5mm from the implant site even after 42 days post-implantation from F3 and H80 was confirmed and deduced to be diffusion/elimination controlled. F3 and H80 demonstrated significant (approximately 30 fold) tumor inhibition and significantly low tumor proliferation index after 41 days of treatment in comparison to sham and placebo controls. The submicron/nanoscale implants are able to demonstrate optimal paclitaxel pharmacokinetics in the brain/tumor with significant tumor inhibition in a glioblastoma xenograft model in mice and hence could be potentially useful to treat highly recurrent GBM.

Journal Article

Animals; Bioware; Image Interpretation, Computer-Assisted; Imaging, Three-Dimensional; Luminescent Proteins; Male; Mice; Microscopy, Fluorescence, Multiphoton; PC-3M-luc; Prostatic Neoplasms; Whole Body Imaging

A new method is described for obtaining a 3-D reconstruction of a bioluminescent light source distribution inside a living animal subject, from multispectral images of the surface light emission acquired on charge-coupled device (CCD) camera. The method uses the 3-D surface topography of the animal, which is obtained from a structured light illumination technique. The forward model of photon transport is based on the diffusion approximation in homogeneous tissue with a local planar boundary approximation for each mesh element, allowing rapid calculation of the forward Green's function kernel. Absorption and scattering properties of tissue are measured a priori as input to the algorithm. By using multispectral images, 3-D reconstructions of luminescent sources can be derived from images acquired from only a single view. As a demonstration, the reconstruction technique is applied to determine the location and brightness of a source embedded in a homogeneous phantom subject in the shape of a mouse. The technique is then evaluated with real mouse models in which calibrated sources are implanted at known locations within living tissue. Finally, reconstructions are demonstrated in a PC3M-luc (prostate tumor line) metastatic tumor model in nude mice.

Journal Article

Aminoquinolines; Animals; B16-F10-luc-G5 cells; Bioware; Cell Line, Tumor; Cell Proliferation; Cell Survival; Culture Media, Conditioned; dendritic cells; Humans; Interferon Type I; Leukocytes, Mononuclear; Lung; Melanoma; Mice; Neoplasms; Oligodeoxyribonucleotides; Quinolines; Subcellular Fractions; Sulfonamides; Toll-Like Receptor 7

Antitumor effects of the toll-like receptor 7 (TLR7) agonist, 852A, were evaluated. Supernatants from human peripheral blood mononuclear cells (PBMC) stimulated with 852A inhibited the proliferation of tumor cell lines Hs294T and 769-P but had no effect on others (786-O and Caki-1). Because addition of 852A directly to the Hs294T cells did not inhibit their proliferation, the mechanism(s) of inhibition of tumor cell proliferation was investigated. Low nanomolar concentrations of 852A stimulated the production of interferon-alpha (IFN-alpha), IFN-inducible protein-10 (IP-10), interleukin-1 receptor antagonist (IL-1Ra), monocyte chemotactic protein-1 (MCP-1), and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) from human PBMCs. Cytokines stimulated by submicromolar concentrations of 852A were sufficient to inhibit Hs294T proliferation. At higher concentrations (3-30 microM), 852A induced the production of IL-12p70, IL-18, and IFN-gamma. PBMC cultures depleted of plasmacytoid dendritic cells (pDC) did not produce IFN-alpha, and their conditioned medium did not inhibit Hs294T proliferation. Anti-IFN-alpha/beta receptor (IFNAR) and anti-IFN-alpha antibodies partially abrogated Hs294T proliferation inhibition by 852A-stimulated PBMC supernatants, whereas separate neutralization of TRAIL, tumor necrosis factor-alpha (TNF-alpha, IFN-gamma, IFN-beta, or IFN-omega had no effect. In vivo, six doses of 852A administration significantly delayed the onset of lung colonies in a B16 melanoma model. Thus, the results demonstrate that the TLR7 agonist 852A inhibits in vitro proliferation of some tumor cells in a pDC-dependent and IFN-alpha-dependent manner and can delay tumor growth in vivo.

Journal Article

FMT; fluorescence molecular tomography; in vivo imaging; cancer

N/A

Journal Article

Amino Acid Transport Systems, Neutral; Animals; Bacterial Proteins; Bioware; Blotting, Northern; Disease Models, Animal; Gene Expression Regulation, Bacterial; Humans; Lac Operon; Mice; Osmolar Concentration; Proline; pXen-5; Recombinant Fusion Proteins; Staphylococcal Infections; Staphylococcus aureus; Symporters; Transcriptional Activation

Staphylococcus aureus can grow virtually anywhere in the human body but needs to import proline through low- and high-affinity proline transporters to survive. This study examined the regulation of the S. aureus putP gene, which encodes a high-affinity proline permease. putP::lacZ and putP::lux transcriptional fusions were constructed and integrated into the genomes of several S. aureus strains. Enzyme activity was measured after growth in media with various osmolyte concentrations. As osmolarity rose, putP expression increased, with a plateau at 2 M for NaCl in strain LL3-1. Proline concentrations as low as 17.4 muM activated expression of the putP gene. The putP::lux fusion was also integrated into the genomes of S. aureus strains that were either SigB inactive (LL3-1, 8325-4, and SH1003) or SigB active (Newman and SH1000). SigB inactive strains showed increased putP gene expression as NaCl concentrations rose, whereas SigB active strains displayed a dramatic decrease in putP expression, suggesting that the alternative sigma factor B plays a negative role in putP regulation. Mice inoculated with S. aureus strains containing the putP::lux fusion exhibited up to a 715-fold increase in putP expression, although levels in the various murine organs differed. Moreover, urine from human patients infected with S. aureus showed elevated putP levels by use of a PCR procedure, whereas blood and some abscess material had no significant increase. Thus, putP is transcriptionally activated by a low-proline and high osmotic environment both in growth media and in murine or human clinical specimens.